Amount of allowance for credit loss on accounts receivable.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense related to estimated loss from loan and lease transactions.

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Loans Held for Investment - Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2011
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	$ 5.1	$ (29.0)
Accounts Receivable, Allowance for Credit Loss	136.6	129.1	$ 144.3	$ 73.0	$ 144.3
Collateral dependent borrowings	20.0		17.5
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	(4.8)	29.2
Balance of defaulted loans under trouble debt restructurings	0.0
Agriculture Portfolio Segment [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	(0.1)	(0.1)
Accounts Receivable, Allowance for Credit Loss	0.6	1.1	0.7	1.6
Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	(2.9)	(8.1)
Accounts Receivable, Allowance for Credit Loss	77.7	65.0	80.5	28.9
Collateral dependent borrowings	9.6		8.9
Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	(1.8)	(16.3)
Accounts Receivable, Allowance for Credit Loss	36.0	38.2	39.2	32.6
Collateral dependent borrowings	8.3		7.8
Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Provision charged to operating expense	(0.1)	(0.1)
Accounts Receivable, Allowance for Credit Loss	0.6	$ 1.1	0.7	$ 1.6
Collateral dependent borrowings	2.1		0.8
Business Assets Pledged as Collateral [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	7.9		7.4
Business Assets Pledged as Collateral [Member] \| Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.0		1.3
Business Assets Pledged as Collateral [Member] \| Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	6.6		6.1
Business Assets Pledged as Collateral [Member] \| Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	1.3		0.0
Real Property Pledged as Collateral [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	11.7		8.6
Real Property Pledged as Collateral [Member] \| Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	9.6		6.5
Real Property Pledged as Collateral [Member] \| Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	1.3		1.3
Real Property Pledged as Collateral [Member] \| Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.8		0.8
Other Property [Member]
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.4		1.5
Other Property [Member] \| Total real estate loans
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.0		1.1
Other Property [Member] \| Commercial
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	0.4		0.4
Other Property [Member] \| Agricultural
Loans and Leases Receivable Recorded Investment, Impaired [Line Items]
Collateral dependent borrowings	$ 0.0		$ 0.0